| ZIP Codes: | 52 ZIP Codes (44 Standard, 6 PO Box, 2 Unique) [See All] |
| Area Codes: | 314 / 557 / 636 |
| Timezone: | Central (GMT -06:00) |
| Local Time: | 2:12:45 PM |
| Population: | 1,028,683 [See All] |
| FIPS: | 29189 |
| CBSA: | St. Louis, MO-IL |
| Land Area: | 539 sq mi |
| Water Area: | 17 sq mi |
| Coordinates: | 38.6504, -90.4031 |
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1,028,683 residents live across 52 ZIPs covering 539 sq mi, served by 13 distinct USPS-recognized cities.
Population moved from 1,031,032 to 1,028,683 from 2014 to 2024 — a -0.2% change. 25 ZIPs gained residents, 18 lost (and 1 held flat).
The county's wealthiest ZIP 63131 (Saint Louis, $225,493 median) and poorest ZIP 63133 (Saint Louis, $39,293) are 8.8 miles apart — a 5.7× income gap across local geography.
Median home values vary 15.2× across this county — from $65,100 in 63133 (Saint Louis) to $988,600 in 63124 (Saint Louis).
Density varies 24× across the county — from 307 people/sq mi in 63038 (Wildwood) to 7,445 in 63105 (Saint Louis).
Educational attainment ranges from 12.8% bachelor's+ in 63136 (Saint Louis) to 85.7% in 63124 (Saint Louis) — the breadth of educational profiles across the area.
Within Missouri, this is the #1 most populous of 116 counties and ranks #3 for median household income .
On the national stage, Saint Louis County is the #46 most populous US county .
Weighted by population, the typical household earns about $93,939 across the county — reflecting what a typical resident sees, not a simple ZIP average.
47.0% of adults age 25+ hold a bachelor's degree or higher (336,809 of 716,373 reporting). The most-educated ZIPs cluster around Saint Louis.
44 Standard delivery, 6 PO Box only, 2 single-entity Unique ZIPs serve this county.
16 ZIPs in this county where more than 60% of adults 25+ hold a bachelor's degree — typically college campuses, research enclaves, or tech corridors.
Median household income spans 5.7× between the wealthiest and poorest ZIPs — a sign of significant intra-county inequality.
| ZIP | City | Type | Population | Median Income | Area (sq mi) | 10-yr Growth |
|---|---|---|---|---|---|---|
| 63021 | Ballwin | Standard | 55,666 | $120,177 | 22.4 | -1.6% |
| 63129 | Saint Louis | Standard | 51,553 | $94,888 | 23.2 | -3.7% |
| 63031 | Florissant | Standard | 50,196 | $70,811 | 14.0 | 1.8% |
| 63123 | Saint Louis | Standard | 49,077 | $77,055 | 12.4 | -1.0% |
| 63026 | Fenton | Standard | 45,354 | $97,553 | 26.7 | 2.8% |
| 63017 | Chesterfield | Standard | 43,243 | $127,095 | 20.8 | 3.8% |
| 63033 | Florissant | Standard | 43,056 | $66,776 | 12.2 | 4.0% |
| 63122 | Saint Louis | Standard | 41,634 | $136,385 | 14.2 | 7.1% |
| 63136 | Saint Louis | Standard | 40,929 | $41,154 | 10.8 | -12.3% |
| 63011 | Ballwin | Standard | 35,920 | $124,454 | 13.8 | -3.8% |
| 63119 | Saint Louis | Standard | 34,181 | $106,183 | 8.5 | 0.8% |
| 63114 | Saint Louis | Standard | 33,969 | $55,870 | 8.8 | -4.6% |
| 63125 | Saint Louis | Standard | 33,294 | $61,624 | 10.7 | 1.2% |
| 63146 | Saint Louis | Standard | 30,678 | $84,756 | 16.2 | 1.2% |
| 63128 | Saint Louis | Standard | 30,540 | $92,359 | 16.1 | 2.8% |
| 63130 | Saint Louis | Standard | 28,910 | $85,823 | 5.1 | -6.1% |
| 63121 | Saint Louis | Standard | 25,008 | $42,701 | 6.8 | -4.8% |
| 63043 | Maryland Heights | Standard | 21,924 | $91,509 | 11.6 | -2.1% |
| 63141 | Saint Louis | Standard | 20,932 | $133,851 | 15.1 | 5.2% |
| 63005 | Chesterfield | Standard | 19,779 | $198,469 | 41.2 | 11.4% |
| 63137 | Saint Louis | Standard | 19,684 | $43,422 | 8.2 | -1.4% |
| 63025 | Eureka | Standard | 19,508 | $125,676 | 42.5 | 48.4% |
| 63034 | Florissant | Standard | 18,908 | $103,905 | 23.6 | 4.5% |
| 63105 | Saint Louis | Standard | 18,875 | $116,439 | 2.5 | 7.6% |
| 63135 | Saint Louis | Standard | 18,381 | $52,328 | 6.3 | -16.4% |
| 63138 | Saint Louis | Standard | 18,233 | $56,096 | 22.0 | -11.0% |
| 63131 | Saint Louis | Standard | 17,935 | $225,493 | 13.5 | 1.1% |
| 63042 | Hazelwood | Standard | 17,813 | $49,453 | 10.8 | -11.5% |
| 63074 | Saint Ann | Standard | 15,793 | $51,610 | 3.9 | 3.8% |
| 63126 | Saint Louis | Standard | 15,452 | $98,852 | 4.6 | 3.5% |
| 63132 | Saint Louis | Standard | 14,283 | $87,385 | 5.3 | 2.0% |
| 63134 | Saint Louis | Standard | 13,059 | $44,680 | 6.3 | -6.0% |
| 63124 | Saint Louis | Standard | 10,839 | $193,942 | 8.9 | 2.1% |
| 63044 | Bridgeton | Standard | 10,324 | $77,819 | 20.1 | -2.0% |
| 63144 | Saint Louis | Standard | 9,505 | $104,438 | 2.3 | 7.8% |
| 63117 | Saint Louis | Standard | 9,261 | $90,921 | 2.4 | 2.5% |
| 63143 | Saint Louis | Standard | 8,975 | $65,861 | 2.0 | -8.2% |
| 63040 | Wildwood | Standard | 8,526 | $133,220 | 3.4 | 1.5% |
| 63088 | Valley Park | Standard | 8,226 | $65,769 | 5.3 | -1.8% |
| 63038 | Wildwood | Standard | 7,107 | $186,450 | 23.2 | 6.4% |
| 63133 | Saint Louis | Standard | 6,569 | $39,293 | 3.3 | -17.6% |
| 63127 | Saint Louis | Standard | 5,268 | $122,663 | 5.9 | 7.7% |
| 63140 | Saint Louis | Standard | 316 | $45,568 | 0.5 | 36.2% |
| 63045 | Earth City | Standard | 0 | — | 2.1 | — |
| 63145 | Saint Louis | PO Box | — | — | 0.0 | — |
| 63032 | Florissant | PO Box | — | — | 0.0 | — |
| 63099 | Fenton | Unique | — | — | 0.0 | — |
| 63151 | Saint Louis | PO Box | — | — | 0.0 | — |
| 63022 | Ballwin | PO Box | — | — | 0.0 | — |
| 63024 | Ballwin | PO Box | — | — | 0.0 | — |
| 63167 | Saint Louis | Unique | — | — | 0.0 | — |
| 63006 | Chesterfield | PO Box | — | — | 0.0 | — |